Evaluation of zomepirac sodium

Abstract

The chemistry, pharmacokinetics, pharmacology, clinical efficacy, adverse effects, physical dependence and tolerance, drug interactions, dosing, and cost of zomepirac sodium (Zomax, McNeil) are reviewed. Zomepirac is a new nonsteroidal anti-inflammatory agent (NSAIA) approved for the treatment of mild to moderately severe pain. The drug is well absorbed when given orally. It undergoes extensive biotransformation in the liver. Zomepirac shares the pharmacology of the other NSAIAs by decreasing prostaglandin synthesis. The efficacy of zomepirac has been demonstrated primarily in acute forms of pain with associated inflammatory processes including postdental-extraction, postpartum, and postoperative pain. Many of these studies have been single-dose evaluations. Zomepirac sodium 100 mg has been reported to be approximately equivalent to one to two tablets of aspirin-phenacetin-caffeine (APC) with codeine 30 mg. In two studies, zomepirac sodium 100 mg compared favorably with morphine sulfate 8 and 16 mg i.m. It has been shown to be superior to aspirin 650 mg in oral-surgery patients. In osteoarthritis, daily doses of zomepirac sodium 400-600 mg are approximately equivalent to aspirin 3200-4800 mg. Zomepirac has side effects similar to high-dose aspirin. Zomepirac is associated with an increased incidence of urogenital symptoms such as dysuria and pyuria. Because of tumorigenicity in rats, the drug is contraindicated in children, pregnant women, and nursing mothers. The drug has not demonstrated any potential for physical dependence, withdrawal, or tolerance. Zomepirac may provide a suitable alternative to aspirin, narcotic/NSAIA combinations, and narcotics in the treatment of mild to moderately severe pain. It is unlikely that zomepirac will replace narcotics in more severe types of pain.